Mitsubishi Lancer Evolution IX. Manual — part 331

ON-VEHICLE SERVICE

ENGINE MECHANICAL

11A-13

4. Attach a three-way joint to the vacuum hose

between the fuel pressure control solenoid valve
and the inlet manifold, and connect a vacuum
gauge.

5. Start the engine and check that idle speed is

within the standard valve.

Standard value: 800

± 100 r/min

6. Check the inlet manifold vacuum.

Limit: Minimum 60 kPa

7. Turn off the ignition switch.
8. Remove the vacuum gauge and the three-way

joint, and then connect the vacuum hose.

9. Remove the M.U.T.-II/III.

LASH ADJUSTER CHECK

M1111002900585

If an abnormal noise (knocking) that seems to be
coming from the lash adjuster is heard after starting
the engine and dose not stop, carry out the following
check.
NOTE:

.

•

If the vehicle is parked on a slope for a long
period of time, the amount of oil inside the lash
adjuster will decrease, and air may get into the
high pressure chamber when starting the engine.

•

After parking the vehicle for long periods, the oil
drains out of the oil passage, and it takes time for
the oil to be supplied to the lash adjuster, so air
can get into the high-pressure chamber.

•

If either of the above situations occur, the abnor-
mal noise can be eliminated by bleeding the air
from inside the lash adjusters.

•

The abnormal noise which is caused by a prob-
lem with the lash adjusters is generated after the
engine is started, and will vary according to the
engine speed. However, this noise is not related
to the actual engine load.

Because of this, if the noise dose not occur immedi-

ately after the engine is started, if it dose not
change in accordance with the engine speed, or if
it changes in accordance with the engine load,
the source of the noise is not the lash adjusters.

•

If there is a problem with the lash adjusters, the
noise will almost never disappear, even if the
engine has been run at idle to let it warm up.

The only case where the noise might disappear is if

the oil in the engine has not been looked after
properly and oil sludge has caused the lash
adjusters to stick.

1. Start the engine.
2. Check that the noise occurs immediately after the

engine is started, and that the noise changes in
accordance with changes in the engine speed.
If the noise dose not occur immediately after the
engine is started, or if it dose not change in
accordance with the engine speed, the problem is
not being caused by the lash adjusters, so check
for some other cause of the problem. Moreover, if
the noise dose not change in accordance with the
engine speed, the cause of the problem is
probably not with the engine (In these cases, the
lash adjusters are normal).

3. While the engine is idling, check that the noise

level does not change when the engine load is
varied.
If the noise level changes, the cause of the noise
is probably parts striking because of worn
crankshaft bearings or connecting rod bearings
(In such cases, the lash adjusters are normal).

4. After the engine has warmed up, run it at idle and

check if any noise can be heard.
If the noise has become smaller or disappeared,
oil sludge could make the lash adjusters stick.
Clean the lash adjusters (Refer to GROUP 11B

−

Rocker Arms and Camshaft

− Rocker Arms and

Camshaft Inspection

P.11B-39

). If not improved,

go to step 5.

5. Bleed air from the lash adjusters (Refer to

P.11A-13

).

6. If the noise has not disappeared even after the air

bleeding, clean the lash adjusters (Refer to
GROUP 11B

− Rocker Arms and Camshaft −

Rocker Arms and Camshaft Inspection

P.11B-39

).

<LASH ADJUSTER AIR BLEEDING>

AKX00328

Good

Min.

Max

AE

1. Check the engine oil and replenish or replace the

oil if necessary.

ON-VEHICLE SERVICE

ENGINE MECHANICAL

11A-14

NOTE:

.

•

If there is an only small amount of oil, air will
be drawn in through the oil screen and will get
into the oil passage.

•

If the amount of oil is greater than normal, then
the oil will being mixed by the crankshaft and a
large amount of air may get mixed into the oil.

•

AK100001

High-pressure chamber

AC

If the oil is degenerated, air and oil will not
separate easily in oil, and the amount of air
mixed into the oil will increase.

•

AKX00330

Gradually open
the throttle valve

Close the throttle valve

Approximately
3,000 r/min

Idle speed

Once

15 s

15 s

Drive pattern for air breeding

AE

If the air which has been mixed in with the oil
due to any of the above reasons gets into the
high pressure chamber of the lash adjuster,
the air inside the high pressure chamber will
be compressed when the valve is open and
the lash adjuster will over-compress, resulting
in abnormal noise when the valve close. This
is the same effect as if the valve clearance is
adjusted to be too large by mistake. If the air
inside the lash adjusters is then released, the
operation of the lash adjusters will return to
normal.

2. Run the engine at idle for 1

− 3 minutes to let it

warm up.

3. With no load on the engine, repeat the drive

pattern shown in the illustration above and check
if the abnormal noise disappears (The noise
should normally disappear after 10

− 30

repetitions, but if there is no change in the noise
level after 30 repetitions or more, the problem is
probably not due to air inside the lash adjusters).

4. After the noise has disappeared, repeat the drive

pattern shown in the illustration above a further 5
times.

5. Run the engine at idle for 1

− 3 minutes and check

that the noise has disappeared.

CRANKSHAFT PULLEY

ENGINE MECHANICAL

11A-15

CRANKSHAFT PULLEY

REMOVAL AND INSTALLATION

M1112001600573

CAUTION

If the vehicle is equipped with the Brembo

™ disc brake, during maintenance, take care not to contact

the parts or tools to the caliper because the paint of caliper will be scratched.

Pre-removal Operation
• Under Cover Removal (Refer to GROUP 51, Front

Bumper

P.51-2

).

• Side Cover Removal

Post-installation Operation
• Drive Belt Tension Check (Refer to

P.11A-7

).

• Side Cover Installation
• Under Cover Installation (Refer to GROUP 51, Front

Bumper

P.51-2

).

AC210941AB

25 ± 4 N·m

1

2

Removal steps

<<

A

>>

1.

Drive belt

2.

Crank shaft damper pulley

CRANKSHAFT PULLEY

ENGINE MECHANICAL

11A-16

REMOVAL SERVICE POINT
<<A>> DRIVE BELT REMOVAL

The following operations will be needed due to the
introduction of the serpentine drive system with the
drive belt auto-tensioner.

AC210996 AB

Auto-
tensioner

Hole A

Hole B

1. Securely insert the spindle handle or ratchet

handle with a 12.7 mm insertion angle into the jig
hole of the auto-tensioner.

2. Rotate the auto-tensioner anti-clockwise and align

hole A with hole B.

CAUTION

To reuse the drive belt, draw an arrow indicating
the rotating direction (clockwise) on the back of
the belt using chalk, etc.

AC210998AB

L-shaped
hexagon
wrench

Auto-
tensioner

3. Insert an L-shaped hexagon wrench, etc. into the

hole to fix and then remove the drive belt.